Urlacher has a Grade 2 hamstring tear that typically keeps players out 3 to 6 weeks, according to Schefter. So it's possible that Urlacher won't be ready to return before the Bears' season is over -- whether that's in the regular season or the playoffs.

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Sources told Schefter "it's not out of the realm of possibility" that Urlacher, 34, could retire after the season. He'll be a free agent in the spring and has had no "substantial" contract talks with the Bears. That could mean Urlacher has played his final game.

It's hard to believe the eight-time Pro Bowl pick, four-time All-Pro selection and 2005 NFL Defensive Player of the Year would call it quits just like that. He seemed to enjoy this particular Bears team, which rolled through the first half of the season.

Chicago has lost three of its last four games and will miss Urlacher. Most players would want at least one more run with this group if an injury ended their season.